package optimizer

import (
	"context"
	"sync"
	"time"

	"xagent/internal/metrics"
	"xagent/internal/scheduler"
)

// ResourceOptimizer manages and optimizes resource usage
type ResourceOptimizer struct {
	scheduler *scheduler.Scheduler
	collector *metrics.Collector
	config    *OptimizerConfig
	mutex     sync.RWMutex
	ctx       context.Context
	cancel    context.CancelFunc
}

// OptimizerConfig contains configuration for the optimizer
type OptimizerConfig struct {
	MaxLoadPerAgent      int
	TargetResponseTime   time.Duration
	OptimizationPeriod   time.Duration
	LoadBalanceThreshold float64
}

// NewResourceOptimizer creates a new resource optimizer
func NewResourceOptimizer(scheduler *scheduler.Scheduler, collector *metrics.Collector, config *OptimizerConfig) *ResourceOptimizer {
	ctx, cancel := context.WithCancel(context.Background())
	return &ResourceOptimizer{
		scheduler: scheduler,
		collector: collector,
		config:    config,
		ctx:       ctx,
		cancel:    cancel,
	}
}

// Start starts the optimization process
func (o *ResourceOptimizer) Start() {
	go o.optimizationLoop()
}

// Stop stops the optimization process
func (o *ResourceOptimizer) Stop() {
	o.cancel()
}

// optimizationLoop runs periodic optimization
func (o *ResourceOptimizer) optimizationLoop() {
	ticker := time.NewTicker(o.config.OptimizationPeriod)
	defer ticker.Stop()

	for {
		select {
		case <-o.ctx.Done():
			return
		case <-ticker.C:
			o.optimize()
		}
	}
}

// optimize performs resource optimization
func (o *ResourceOptimizer) optimize() {
	// Get current system metrics
	systemLoad := o.scheduler.GetSystemLoad()
	metrics := o.collector.GetMetrics()

	// Check for overloaded agents
	if o.needsLoadBalancing(systemLoad) {
		o.balanceLoad(systemLoad)
	}

	// Check response times
	if o.needsScaling(metrics) {
		o.adjustResources(metrics)
	}

	// Update optimization metrics
	o.updateOptimizationMetrics(systemLoad, metrics)
}

// needsLoadBalancing checks if load balancing is needed
func (o *ResourceOptimizer) needsLoadBalancing(systemLoad map[string]interface{}) bool {
	avgLoad := systemLoad["average_load"].(float64)
	maxLoad := systemLoad["max_load"].(int)

	// If max load is significantly higher than average
	return float64(maxLoad) > avgLoad*o.config.LoadBalanceThreshold
}

// balanceLoad performs load balancing
func (o *ResourceOptimizer) balanceLoad(systemLoad map[string]interface{}) {
	agentLoads := systemLoad["agent_loads"].(map[string]int)

	// Find overloaded and underloaded agents
	var overloaded, underloaded []string
	avgLoad := systemLoad["average_load"].(float64)

	for agentID, load := range agentLoads {
		if float64(load) > avgLoad*o.config.LoadBalanceThreshold {
			overloaded = append(overloaded, agentID)
		} else if float64(load) < avgLoad/o.config.LoadBalanceThreshold {
			underloaded = append(underloaded, agentID)
		}
	}

	// Redistribute tasks
	for _, overAgent := range overloaded {
		for _, underAgent := range underloaded {
			o.redistributeTasks(overAgent, underAgent)
		}
	}
}

// redistributeTasks moves tasks between agents
func (o *ResourceOptimizer) redistributeTasks(fromAgent, toAgent string) {
	// Implementation depends on task migration capabilities
}

// needsScaling checks if system needs scaling
func (o *ResourceOptimizer) needsScaling(metrics map[string]interface{}) bool {
	avgResponseTime := metrics["average_latency"].(time.Duration)
	return avgResponseTime > o.config.TargetResponseTime
}

// adjustResources adjusts system resources
func (o *ResourceOptimizer) adjustResources(metrics map[string]interface{}) {
	// Implementation depends on scaling capabilities
}

// updateOptimizationMetrics updates optimization-related metrics
func (o *ResourceOptimizer) updateOptimizationMetrics(systemLoad, metrics map[string]interface{}) {
	optimizationMetrics := map[string]interface{}{
		"load_balance_score":   o.calculateLoadBalanceScore(systemLoad),
		"resource_utilization": o.calculateResourceUtilization(systemLoad),
		"performance_score":    o.calculatePerformanceScore(metrics),
		"optimization_actions": o.getOptimizationActions(),
	}

	o.recordMetrics(optimizationMetrics)
}

// Helper methods for metric calculations
func (o *ResourceOptimizer) calculateLoadBalanceScore(systemLoad map[string]interface{}) float64 {
	// Implementation
	return 0.0
}

func (o *ResourceOptimizer) calculateResourceUtilization(systemLoad map[string]interface{}) float64 {
	// Implementation
	return 0.0
}

func (o *ResourceOptimizer) calculatePerformanceScore(metrics map[string]interface{}) float64 {
	// Implementation
	return 0.0
}

func (o *ResourceOptimizer) getOptimizationActions() []string {
	// Implementation
	return nil
}

func (o *ResourceOptimizer) recordMetrics(metrics map[string]interface{}) error {
	return o.collector.RecordEvent("optimization", metrics)
}
